77212823 has 4 divisors (see below), whose sum is σ = 77513520. Its totient is φ = 76912128.

The previous prime is 77212813. The next prime is 77212829. The reversal of 77212823 is 32821277.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 77212823 - 2⁸ = 77212567 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77212823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77212829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 149963 + ... + 150476.

It is an arithmetic number, because the mean of its divisors is an integer number (19378380).

Almost surely, 2^77212823 is an apocalyptic number.

77212823 is a deficient number, since it is larger than the sum of its proper divisors (300697).

77212823 is a wasteful number, since it uses less digits than its factorization.

77212823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300696.

The product of its digits is 9408, while the sum is 32.

The square root of 77212823 is about 8787.0827354703. The cubic root of 77212823 is about 425.8236815056.

The spelling of 77212823 in words is "seventy-seven million, two hundred twelve thousand, eight hundred twenty-three".